Manto nevoso

Old Ski Bowl - Saint Germaine Ridge

Eric FalconerMount Shasta
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Quick report

Today's observation brought me to the Old Ski Bowl, where I assessed different aspects and elevations for signs of wind slab and wet-loose snow instability. Several small point releases and actively shedding roller balls were observed near and below treeline on steep, rocky east, south, and west-facing slopes. Snow surfaces began to rapidly warm and soften as the day advanced. Softening snow surfaces were experienced on all aspects and elevations, being most pronounced near treeline. Above treeline, strong winds were observed actively blowing snow and loading start zones on southerly aspects. Previous wind-loaded slopes were evident among alpine terrain, and a large amount of wind effect is present.

Rapid warming caused surface snow to destabilize on steep solar-lit slopes.

Weather

Air Temp
54
Cloud Cover
few
Wind Loading
moderate
Recent Snowfall
0
Snow Avail For Transport
moderate amounts

High pressure and relentless north-northeast winds kicked off the day. By early afternoon, (1300 hours), wind intensity above treeline subsided and less blowing snow was observed. This is likely due to a shift in wind direction from north to south. Clear and sunny skies prevailed, allowing for ample amounts of solar heating.

Snowpack

The snowpack near and below treeline has been mostly unscathed by the wind, compared to above treeline, where a large amount of wind effect exists. However, the snow remains relatively soft despite all the sastrugi and variable surfaces. 
 
Surfaces conditions are becoming wet and damp. Pinwheels were easy to initiate on steep slopes and rapidly collected surrounding snow. On east, south, and west aspects near treeline, roughly 4 inches (10cm) of wet surface snow was observed overriding dryer snow. As radiative heating continues, I would suspect saturation levels to increase. North aspects also held damp surfaces, but not to the extent as solar-lit slopes. Surfaces continued to soften and weaken during the duration of my outing, presenting wet and slushy conditions. 
 
A pit dug on a south aspect at 8,600 feet reviled a fragile crust, 50 cm (20") down. Propagation was achieved on the snow underneath the crust with hard force. It's unlikely that this layer holds much risk at this time, nevertheless, forecasters will continue to monitor it as time progresses.